Know Before You Go

Bighorn sheep (Ovis canadensis) are a symbol of resilience within the rugged American West, carrying a dramatic history of near extinction on their crown of horns. A ram's horns can weigh up to 30 pounds, making these accessories account for about 20 percent of their body weight. The horns serve offensive and defensive purposes during mating season, when two males charge at each other at up to 40mph. Their flexible skulls absorb the collisions to protect their brains. Impressively, these dominance rituals have been known to last as long as 20 hours until one male concedes!

Prior to the mid-1800s, bighorn sheep were abundant throughout the Rocky Mountains, with a range that extended from Alaska to northern Mexico and into the snowfields of Canada. Their population was estimated to be two million, spread among distinct social groups comprising 10 to 100 members. European expansion westward triggered a decline in the species with the popularity of trophy hunting. Then, ranchers began acquiring land in the mountain valleys, degrading wildlife corridors and critical bighorn habitat as they cultivated. The introduction of domestic sheep delivered the final blow. Wild herds had to compete for forage, while contending with disease transmission from invading livestock.

By 1960, numbers were reduced to fewer than 18,000 individuals. Today, bighorn populations have diminished more than 70 percent from historic levels. Despite intensive management and restoration efforts, populations continue to struggle. Research concludes that wild bighorn herds are most vulnerable to pneumonia carried by domestic sheep. Pneumonia outbreaks result in mortality rates up to 90 percent. Conservationists agree that the separation of domestic and bighorn sheep is vital to ensuring bighorn herd health. This can be achieved through enacting buffer zones, endorsing public policies, working with private landowners and increasing public education about the risks of contact between species.